ICAR Technical Series no. 7 - Nitra Proc.

Milking variables in relation to teatsresponse (Mayer et al., 1984; Svennersten and Claesson, 1990). Accordingto Lefcourt (1982), the effect of teat stimulation on sympathetic tone in themammary gland is a second milk letdown mechanism. In addition tooxytocin causing milk letdown, the nervous system also plays a role inrate of milk flow through the teat canal (Bruckmaier and Blum, 1998). Aminimum of 12-15 seconds of teat contact time is required for sufficientnerve stimulation to ensure adequate oxytocin release and a good milkejection response (Mein and Reid, 1996). Premilking cow preparation isproven to be an important step in achieving maximum milk yield, qualityand udder health. Units should be attached within a window of 60 to90 seconds from beginning of udder preparation process to take advantageof oxytocin stimulated by good teat manipulation (Rasmussen et al., 1992).The purpose of this experiment was to investigate the effect of the timetaken to manually clean and dry the teats before the unit is attached andthe time from the beginning of the cow preparation process until unitattachment on milk flow time, first minute milk flow rate, average milkflow rate, milk yield and somatic cell count in milk.Material andmethodsA field study was carried out on 84 black and white dairy cows randomlychosen. Cows were held in a two tie-stall barn and milked to a pipeline bya set of four milking units MilkMaster with automatic teatcups detachers.All cows were milked using the same milking routine consisting of forestripping of three to five squirts from each teat followed by teat cleaningwith a different total duration.The machine was attached in a different time for each cow after preparation.The time taken to manually clean and dry the teats before the unit isattached is referred to as “Prep time” and the time from the beginning ofthe cow preparation process until unit attachment is referred to as “Preplag time” (Reneau and Chastain, 1995).Time studies were conducted for three consecutive days at evening milking.Prep time, Prep lag time, milk flow time from individual quarters, firstminute milk flow rate, average milk flow rate, total milking time and milkyield were recorded. On the fourth day milk samples were taken duringevening milking in order to determinate somatic cell counts usingFossomatic 4000.The effect of prep time divided into two classes (to 30 sec., >30 sec.) andprep lag time into two classes (to 60 sec., > 60 sec.) on first minute milkflow rate, average milk flow rate, total milk yield and total milking timewas investigated.Results are presented tables as means ± SD. For statistical evaluationsSTATISTICA 97 software was used. Mean differences of different classeswere tested for significant differences using the Duncan’s Test.90Conference on "Physiological and technicalaspects of machine milking"